FERNANDINA Galápagos Islands, Ecuador 0.37°S, 91.55°W; summit elev. 1,476 m; All times are local (= UTC - 5 hours)

Reports from 2005: | May | 


Fernandina Eruption History Information from the Si/USGS Global Volcanism Program


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11-17 May 2005

On 13 May the Charles Darwin Research Station (CDRS) received news that Fernandina, an island volcano in the Galapagos, had begun erupting that morning. Satellite photos showed a large cloud extending to the NW. On 14 May a joint Galápagos National Park and CDRS team flew over the eruption site. On approaching the island a large convection cloud could be seen rising above the main cloud layer above the volcano, but the caldera and rim could not be seen. On passing below the cloud, lava flows could be seen on the SW and S slopes. The first flow seems to have occurred more or less where the last eruption started in 1995, high on the SW slope, but from a circumferential fissure near the rim. The fissure itself could not be seen owing to the cloud on the rim, but map analysis suggests that the fissure was about 4.5 km long around the rim or just below it, with the first flows emanating from the W part of the fissure, and the latest flows from the E part. The flows descended the steepest part of the slopes quickly, and ponded on the gentler outer skirt of the island. The closest point that the lava had approached the sea on the 14th was 5.5 km from the coast. Lava passing through vegetated areas has caused small fires, but these have not spread far from the lava tongues themselves before going out. Most of the new flows have passed over unvegetated older lava.

A short time after the volcano started to erupt, the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) flying on the OrbView-2 satellite captured an image showing a thick cloud of ash and steam fanning out W of the volcano, with a smaller, slightly darker plume blowing S. This darker plume may be more ash-rich than the larger plume, or it may be smoke from fires ignited by lava flows. Washington VAAC notices reported that the W-directed plume rose to about 5 km (17,000 feet) altitude on the afternoon of 13 May, and the S-directed plume went to 9 km (30,000 feet); both were visible later that day in satellite imagery more than 200 km from the volcano.

Thermal anomalies detected in MODIS satellite imagery, provided by the University of Hawaii, abundant on 14 and 15 May, were not evident on the 16th. Hot spots were again identified at the rim and down the S flank on 17 May.

Source: Alan Tye, Charles Darwin Research Station; NASA Earth Observatory; Washington Volcanic Ash Advisory Center;